Vehicle-mounted asphalt cutter



Nov. 28, 1967 E. G- M CLURE VEHICLE-MOUNTED ASPHALT CUTTER Filed Feb. 2, 1967 i K III- Mmvrae 405 GAE/V M90025 avjifzm firroeuzra United States Patent ABSTRACT OF THE DISCLOSURE An asphalt cutter comprising a movable vehicle, an upwardly extending boom pivotal about its lower end in horizontal and verticalplanes, a downwardly extending boom connected at a point adjacent its upper end to the upper endv of said upwardly extending boom constructed and. arranged to pivot in a vertical plane, and a rotatable disc, connected to. the lower end of the downwardly extending boom, having its axis of rotation, disposed in a horizontal. plane.

BACKGROUND OF THE INVENTION In the past, when it was desired to cut through the surface of a layer of asphalt or similar pavement compound, ithas been customary to utilize air hammers or similar apparatus motivated by high pressure air to break the crust oi the asphalt. The cutting bit of the air hammer was placed over the portion of the asphalt to be cut, and the cutting action was attained by rapid reciprocation of the cuttingbit. The reciprocation ofthe. cutting bit performed a combination impact and sawing effect on the asphalt until the layer of asphalt was completely out through, whereupon the cutting bit was removed from the cut made in the asphalt and repositioned to create another cut coextensive with the previously cut area. This procedure resulted in somewhat jagged individual cuts 'in the asphalt, and individual cuts were rarely aligned with one another to create a smooth out throughout a single SUMMARY OF THE INVENTION This invention comprises an asphalt cutter including a movable vehicle, an upwardly extending boom connected at its lower end to the moving vehicle and pivotal about its lower end in both horizontal and vertical planes, a downwardly extending boom connected adjacent its upper end to the upper end of the upwardly extending boom and pivotal in a vertical plane about the end of the upwardly extending boom, and a cutting member rotatably con nected to the lower end. of the downwardly extending boom. The cutting member is disc-shaped and rotatable about a horizontal axis. The cutting member can be moved in a downward direction by means of the booms so that it engages the upper surface of a layer of asphalt and moved toward or away. from the movable vehicle to slice through the surface of the asphalt. The vehicle may be moved'in a direction substantially normal to the axis of the cutting member so as to push or pull the cutting member along through the surface of the asphalt. If the cutting member does not initially pierce the layer of asphalt to. its fullest extent, the booms of the vehicle may be manipulated so that the cutting member retraces its previous cut in the asphalt to deepen the cut, or the 3,355,214 Patented Nov. 28, 1967 ICC vehicle may be moved to retrace its previous path to cause the cutting member to re-engage its initial cut in the asphalt.

The cutting. member may be removed from the. booms of the vehicle and replaced with a conventionalv digging tool, such as a pivotal buclget, and, they booms. and movable eh l ay e uti ed o p r orm h ti n. of removing the asphalt cut by the cutting member and digging a hole or trench in the area below that previously 0ccupied by the removedasphalt.

Thus, it is an object of this invention to provide apparatus for cutting asphalt or similar pavement, compound that does not require a source of compressed. air.

Another object of this invention is to provide an at tachment for a tractor or similar vehicle for cutting asphalt.

Another object of this invention is to provide apparatus for creating an elongate cut in the su tface of asphalt Another object of this invention is to provide apparatus for forming a continuouscut in the surface of a layer of asphalt.

Another object of this invention is to provide apparatus for economically and expediently cutting through a layer of asphalt.

Other objects, features and advantages of the present invention will become apparent upon reading the following specification, taken in conjunction with the accompanying drawing.

BRIEF DESCRIPTION OF THE' DRAWING FIG. 1 is a side elevational view of the asphalt cutter attached to a tractor.

FIG. 2 is a side elevational view of the cutting member.

FIG. 3- is an end view of the cutting member.

DESCRIPTION OF THE EMBODIMENT of the vehicle to which the cutter 10 is: to be connected is. that a sourcev of power must be available to. create; a hydraulic pressure or to drive the. pump of the asphalt cutter to operate the various hydraulic pistons of the cutter.

Cutter 10 comprises a mounting and. control structure 12 which is connected to the, tractor 11, at the. rear of the tractor. The mounting and control structure 12 includes a pair of normally downwardly extendingsupport legs 14 extending laterally thereof. Feet 15 are rigidly connected to support legs14, and hydraulic cylinders:,16 are connected between feet 15 and the; mounting and control structure 12, to adjustably control the attitude of support legs 14.

Support boom 18 is'connected at its lower end 19 to mounting and control. structure. 12; The connection between lower end 19- of support boom 18 and mounting and control structure 12 is such as to provide pivotal movement of support. boom 18 in both horizontal and vertical directi ns. Means (not shown) for pivoting support boom 18v in a horizontal direction areenclosedin mounting and control structure 12, while cylinder 20 and piston rod 21 are connected between support boom 18 and mounting and control structure 12 to provide the pivotal movement of support boom 18' ina vertical plane.

Workingboom 22 is. connected at a point intermediate its ends o t e uppe nd unport oom Th connection between support boom 18 and working boom 22 is such that working boom22 is pivotal in a vertical plane. The upper end 26 of working boom 22 extends beyond the upper end of support boom 18, and hydraulic cylinder 28 is connected to support boom 18 and piston rod 29 is connected to the upper end 26 of working boom 22 in such a manner that movement of piston rod 29 causes pivotal movement of working boom 22 about support boom 18.

The lower end 30 of working boom 22 has connected thereto cutting assembly 31. As is shown in FIGS. 2 and 3, cutting assembly 31 comprises a U-shaped support casing 32 which includes a base portion 34 and upwardly extending leg portions 35 and 36. Cutter supports 37 and 38 extend in a downward direction from base portion 34 of support casing 32. Cutter supports 37 and 38 are spaced inwardly on base portion 34 from upwardly extending leg portions 35 of the support casing 32, and support webs 39 and 40 extend between cutter supports 37 and 38 and base portion 34 of support casing 32.

Cutter supports 37 and 38 define a space 41 therebetween to accommodate cutter, cutting disc or bit 42. Cutting disc 42 defines a central aperture (not shown) and cutter supports 37 and 38 define aligned apertures (not shown). The aperture of cutting disc 42 is aligned with the apertures of cutter supports 37 and 38, and an axle 43 is inserted through the aligned apertures and fastened to cutter supports 37 and 38 by means of nuts 44. The axle is of conventional construction and defines a bearing surface such that cutting disc 42 is free to rotate within space 41 defined by the cutter supports 37 and 38.

The upwardly extending leg portions 35 and 36 of support casing 32 define spaced apertures 45 and 46. The apertures 45 of each leg portion 35 and 36 are in alignment with each other while the apertures 46 of each leg portion 35 and 36 are in alignment with each other.

Cutting assembly 31 is connected to the lower end 30 of working boom 22 by inserting the lower end 30 between the upwardly extending leg portions 35 and 36 of the support casing 32 of the cutting assembly 31 and inserting a pivot pin 50 through an aperture (not shown) in the lower end 30 of the working boom 22 and one of the pairs of aligned apertures 45 or 46 of the leg portions of the support casing 32. Hydraulic cylinder 51 is connected to working boom 22, intermediate its ends, and piston rod 52 extends outwardly of cylinder 51. Guide lever 54 is pivotally connected by means of pivot pin 55 at one of its ends to working boom 22, and at its other end to piston rod 52 by means of pivot pin 56. A pair of links 58 are connected to each end of pivot pin 56, and to upwardly extending leg portions 35 and 36 of support casing 32 by means of connecting rod 59 extending through one of the pairs of apertures 45 or 46 of support casing 32. Thus, cylinder 51, piston rod 52, guide lever 54 and links 58 determine the attitude of cutting assembly 31 with respect to working boom 22.

Cutting disc 42 includes a sharpened outer periphery 60 formed of hardened steel. The outer rim portion 61 is sharply tapered so that the periphery 60 of the disc forms a sharp cutting edge which easily penetrates the surface to be cut by the asphalt cutter. The central portion 62 of disc 42 defines an annular recess 63 inwardly of the rim portion 61 and is convex so as to be thicker than its outer portion so that the axle extending through the center of the disc is provided with a large bearing surface.

The mounting and control structure 12 of the asphalt cutter 10 includes a plurality of control valves (not shown) which are operated by levers in a conventional manner. Movement of levers 64 functions to open or shut control valves that communicate the various cylinders 16, 20, 28 and 51 with a hydraulic pump (not shown) in the mounting and control structure 12 that is driven by the power 'takeoff from tractor 11. In this manner, the various movements of the support boom 18, working boom 22 and cutting assembly 31 are carried out.

4 OPERATION When a layer of asphalt, or similar pavement compound, is to be cut, tractor 11 is positioned adjacent the area to be cut and support legs 14 of the asphalt cutter 10 adjusted by means of their cylinders 16 to engage the ground or asphalt surface at the rear of the tractor 11 to support the asphalt cutter 10. Levers 64 are manipulated to control the movement of support boom 18, working boom 22 and cutting assembly 31 by means of the various cylinders 20, 28 and 51. Booms 18 and 22 are manipulated so that cutting disc 42 engages the surface of the asphalt at the point at which it is to be cut, and cutting disc 42 is thrust in a downward direction by manipulation of support boom 18 and working boom 22 so that it penetrates the surface of the asphalt. Working boom 22 can be pivoted about support boom 18 so as to walk cutting disc 42 toward or away from tractor 11. As working boom 22 moves in this manner, cutting disc 42 will rotate about its axle, and its sharpened edge 60 will penetrate the asphalt in its path. If the entire layer of asphalt is not cut through on the initial opeartion of the asphalt cutter 10, working boom 22 can be oscillated back and forth about the upper end of support boom 18 so that cutting disc 42 repeatedly retraces its initial cut in the surface of the asphalt until the cutting disc 42 penetrates the layer of asphalt a distance sufiicient to completely out through the layer.

If the asphalt to be cut is particularly diflicult to cut, cutting disc 42 may engage the surface of the asphalt and cylinder 51 operated in a manner to oscillate cutting assembly 31 about the lower end of working boom 22 to move cutting disc 42 in a short path back and forth over the surface of the asphalt until the asphalt is penetrated by the cutting disc. After the initial penetration is made, working boom 22 may be oscillated to lengthen the cut. If the layer of the asphalt is relatively soft or thin so that it is easily penetrated by cutting disc 42, support legs 14 of tractor 11 can be retracted by cylinders 16 and tractor 11 moved along the surface of the asphalt in the direction in which a cut is desired so that cutting disc 42 is walked through the layer of asphalt by the tractor. If the asphalt cannot be cut this easily, after the initial out has been made tractor 11 can be repositioned so that cutting disc 42 is positioned to lengthen the initial cut.

After the desired cuts have been made through the layer of asphalt, cutting disc 42 is withdrawn from the asphalt and cutting assembly 31 may be entirely removed from working boom 22 or the entire asphalt cutter 10 may be removed from tractor 11. Thus, tractor 11 is available to perform its various other functions of dirt removal, leveling, etc. If desirable, booms 18 and 22 may be equipped with other tools, such as scoops, digging buckets, etc. Thus, booms 18 and 22 may be utilized to remove the asphalt cut by cutting assembly 31 and dig below the level of the asphalt, as when laying pipes or performing other subsurface operations.

The particular assembly shown in FIG. 1 is especially useful to sewer contractors because of its versatility. A sewer contractor must cut through the road surface, dig below the road surface and lay the proper pipes and catch basins, etc. for the construction of a sewer line. A tractor similar to that shown in FIG. 1 can be mounted with asphalt cutter 10 to perform the necessary cutting of the layer of asphalt, subsequently fitted with a scoop bucket to dig below the surface of the asphalt, and the asphalt and dirt removed from the ground may be loaded, moved or otherwise handled by the front end equipment attached to the tractor 11. Thus, the sewer contractor may complete his job without the use of an air hammer and its necessary air compressor.

It should be understood that while a particular tractor 11 has been illustrated in combination with asphalt cutter 18, various other vehicles may be utilized to support and supply power to the asphalt cutter. Furthermore, while a particular arrangement of hydraulic cylinders and booms have been shown forthe manipulation of cutting assembly 31, various other arrangements may be utilized to move and manipulate cutting assembly 31 in the same or a similar manner.

It will be obvious to those skilled in the art that many variations may be made in the embodiment chosen for the purpose of illustrating the present invention without departing from the scope thereof as defined by the appended claims.

What is claimed as invention is:

1. Apparatus for cutting a hardened surface comprising a vehicle, an upwardly extending support member pivotally connected at its lower end to said vehicle, a downwardly extending support member pivotally connected to the upper end of said upwardly extending support member, (and) a cutting member rotatably connected to the lower end of said downwardly extending support member, said cutting member being rotatable about a laterally extending axis, and means for pivoting said cutting member about the lower end of said downwardly extending support member in a plane extending normal to said laterally extending axis.

2. The invention of claim 1 wherein said cutting member is a centrally apertured disc and said support members and said vehicle include means for pivoting said support members in vertical planes about said vehicle.

3. In a movable vehicle comprising a support, an upwardly extending boom pivotally supported at its lower end by said support, a downwardly extending boom pivotally supported at its upper end at the upper end of said upwardly extending boom, means for pivoting said upwardly extending boom with respect to the vehicle, and means for pivoting said downwardly extending boom with respect to said upwardly extending boom; the combination therewith of a cutting disc rotatably supported by said downwardly extending boom, and means for pivoting said cutting disc about a horizontally disposed axis at the lower end of said downwardly extending boom.

4-. The invention of claim 3 wherein said cutting disc comprises a centrally apertured disc, a housing defining a U-shaped frame connected to said downwardly extending boom and a pair of disc support members extending outwardly from said frame and defining a pair of aligned apertures, and a connecting member extending through said aligned apertures and the aperture of said disc.

References Cited UNITED STATES PATENTS 1,003,149 9/1911 Pascal 299-75 X 2,808,253 10/ 1957 Miller 29976 2,890,872 6/1959 Hall 299-40 3,067,989 12/ 1962 Moench 29940 3,271,079 9/1966 Simmons 29940 ERNEST R. PURSER, Primary Examiner. 

1. APPARATUS FOR CUTTING A HARDENED SURFACE COMPRISING A VEHICLE, AN UPWARDLY EXTENDING SUPPORT MEMBER PIVOTALLY CONNECTED AT ITS LOWER END TO SAID VEHICLE, A DOWNWARDLY EXTENDING SUPPORT MEMBER PIVOTALLY CONNECTED TO THE UPPER END OF SAID UPWARDLY EXTENDING SUPPORT MEMBER, (AND) A CUTTING MEMBER ROTATABLY CONNECTED TO THE LOWER END OF SAID DOWNWARDLY EXTENDING SUPPORT 